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Re: Log Error ( ? )

  • To: mathgroup at smc.vnet.net
  • Subject: [mg78945] Re: [mg78883] Log Error ( ? )
  • From: Murray Eisenberg <murray at math.umass.edu>
  • Date: Fri, 13 Jul 2007 06:07:33 -0400 (EDT)
  • Organization: Mathematics & Statistics, Univ. of Mass./Amherst
  • References: <200707120911.FAA08031@smc.vnet.net>
  • Reply-to: murray at math.umass.edu

Umm...

   Log[x-1]-2 = 0

is equivalent to x = 1+E^2, and N[1+E^2] gives 8.38906.

Only "bug" is in your thinking the intercept should be 101.

Larry wrote:
> Hi,
> 
> I had a question about something I found in Mathematica 5.2...   I was plotting Log[x-1]-2 with x = {0,10} and y =  {-10,5} and strangely found that the graph crossed the x-axes at approximately x == 8  ...
> 
> It should be 101 of course, but it seemed like 8.   Then I did an Nsolve with the equation set to 0, and low and behold got an answer x == 8.38906.
> 
> Is this a bug in mathematica or am I missing something here?
> 

-- 
Murray Eisenberg                     murray at math.umass.edu
Mathematics & Statistics Dept.
Lederle Graduate Research Tower      phone 413 549-1020 (H)
University of Massachusetts                413 545-2859 (W)
710 North Pleasant Street            fax   413 545-1801
Amherst, MA 01003-9305


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